1. Field of the Invention
This invention relates to a device for measuring the external threads of a threaded fastener.
2. Description of the Prior Art
Threaded fasteners such as screws and threaded bolts must meet minimum tolerances in order to avoid damage and to ensure proper functioning of the fastener during tightening and loosening operations. For this reason, thread gages have been designed for gaging the diameter of the screw threads. While there are various devices for measuring the external threads of these fasteners, they are often complex in design. The devices usually involve gaging segments that are pivotally mounted on arms so that the segments can be open and closed around the threaded fastener. Often, removal and replacement of the segments from such devices is difficult and time consuming.
What is therefore needed is an external thread gage that is reliable and simple in design and that allows the gage segments to be easily removed and replaced.